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Hello everyone, I have been having an over heating issue if sitting at an idle for a long period of time. 15 minutes or so, but when driving around as far as the stock temp gauge is reading it is fine. mods done to the car are... 2.4l 4g64 with a 4g63 head with S3 cams, +1 intake and exhaust valves. I am also running a Koyo half rad with a 1200 cfm fan that I just installed the other day. It has seemed to help a little bit with the issue but has not solved it. I have the 03 outlander water pump. And I am running a cometic 87mm head gasket. I replaced the head gasket over the winter time and the problem is still here. I have not replaced the thermostat but i don't believe that to be my issue because the car will only over heat if idling for a long period of time. Any help or suggestions would be awesome. I would love to drive the car to work but with all the traffic I sit in the car just starts to get hot is no fun.
I'm running Mishi half rad on my 63, factory oil cooler and a mishi slim fan 1150cfm with no shroud and I never have overheating issues, even when im in hot 110F+ traffic for hours. That's a 2.0l with OE water pump though, so ymmv.
Do you have a shrouded fan or just a slim fan mounted behind the rad?
I'm running Mishi half rad on my 63, factory oil cooler and a mishi slim fan 1150cfm with no shroud and I never have overheating issues, even when im in hot 110F+ traffic for hours. That's a 2.0l with OE water pump though, so ymmv.
Do you have a shrouded fan or just a slim fan mounted behind the rad?
I have just the same fan I believe. I think it might have something to do with my rad cap. I just jacked up the front end and let it idle to get any air bubbles out and it will idle for like 20 minutes just fine before I shut it off and as soon as I put the cap back on a few minutes later it starts to get hot again.
I have just the same fan I believe. I think it might have something to do with my rad cap. I just jacked up the front end and let it idle to get any air bubbles out and it will idle for like 20 minutes just fine before I shut it off and as soon as I put the cap back on a few minutes later it starts to get hot again.
Are you boiling over? Bad rad cap would definitely cause overheating at idle. I recommend pressure testing it if possible.
Are you boiling over? Bad rad cap would definitely cause overheating at idle. I recommend pressure testing it if possible.
It doesn't seem to be. just weird that if the cap is off with the funnel on in my garage and its fine. Ill let the fan come on and off a few times and all good. put the cap back on go around the block park in my driveway and after about 5 minuets it gets hot again. I am going to bring my kit home from work tonight and do a pressure test.
I believe my issue has been solved. Did a pressure test and everything was fine, no leaks. Jacked up front end and tried to bleed system one more time. Only a few small bubbles came out, put on a different radiator cap from a older stock radiator I had laying around. Went for a drive around the block and then let it sit and idle in my driveway for about 20-30 minutes. Stock temp gauge stayed just below half. It did rise to about half then went right back down when the fan kicked back on. Think I had a mixture of a bad radiator cap and a little bit of an air bubble in the system.
ideally you want 2400cfm from the fan (puller) in order to remove the heat. Likely the 1200cfm just can't pull enough heat from the radiator so you are on the edge. To the extent you can, force the fan to draw in cooler air from the front of the car instead of heat coming from the engine bay. This will likely require that you make an aluminum shield on the header side of the radiator to block it from ingesting engine heat. Also, make sure, to the extent you can, seal the radiator with foam around the edges between the radiator and front cross member to limit hot engine air from entering the radiator. All of these little things help a lot.
See the foam in my pic below that I purchased from Lowes that seals the radiator edges so it can't suck in engine heat.
ideally you want 2400cfm from the fan (puller) in order to remove the heat. Likely the 1200cfm just can't pull enough heat from the radiator so you are on the edge. To the extent you can, force the fan to draw in cooler air from the front of the car instead of heat coming from the engine bay. This will likely require that you make an aluminum shield on the header side of the radiator to block it from ingesting engine heat. Also, make sure, to the extent you can, seal the radiator with foam around the edges between the radiator and front cross member to limit hot engine air from entering the radiator. All of these little things help a lot.
See the foam in my pic below that I purchased from Lowes that seals the radiator edges so it can't suck in engine heat.
With the Koyo Half radiator the biggest fan that I can seem to fit is a 13" fan and I have only found puller fan to provide around 1300cfm. And I have solved my issue but thank you for the information. Your set up looks very clean.
I'm running a 2.4 with an evo 8 head and kelford 276 high cams in my car. I run the stock evo 9 head gasket, 4g63 gates water pump w/adapter plate, mishimoto half sized radiator, mishimoto race thermostat, and OEM fan. Been running this setup for about 3 years now and have never had any issue what so ever with overheating.
